2D Dual‐Metal Zeolitic‐Imidazolate‐Framework‐(ZIF)‐Derived Bifunctional Air Electrodes with Ultrahigh Electrochemical Properties for Rechargeable Zinc–Air Batteries

Abstract

Here first a 2D dual-metal (Co/Zn) and leaf-like zeolitic imidazolate framework (ZIF-L)-pyrolysis approach is reported for the low-cost and facile preparation of Co nanoparticles encapsulated into nitrogen-doped carbon nanotubes (Co-N-CNTs). Importantly, the reasonable Co/Zn molar ratio in the ZIF-L is the key to the emergence of the encapsulated microstructure. Specifically, high-dispersed cobalt nanoparticles are fully encapsulated in the tips of N-CNTs, leading to the full formation of highly active Co-N-C moieties for oxygen reduction and evolution reactions (ORR and OER). As a result, the obtained Co-N-CNTs present superior electrocatalytic activity and stability toward ORR and OER over the commercial Pt/C and IrO 2 as well as most reported metal-organic-framework-derived catalysts, respectively. Remarkably, as bifunctional air electrodes of the Zn-air battery, it also shows extraordinary charge-discharge performance. The present concept will provide a guideline for screening novel 2D metal-organic frameworks as precursors to synthesize advanced multifunctional nanomaterials for cross-cutting applications.

CuCo2S4 Nanosheets@N‐Doped Carbon Nanofibers by Sulfurization at Room Temperature as Bifunctional Electrocatalysts in Flexible Quasi‐Solid‐State Zn–Air Batteries

“…[19,[38][39][40][41][42] With the incorporation of Cu, the CuCo-based electrocatalysts display a higher catalytic activity due to their tailored electron transfer between Cu and Co ions. [19,[38][39][40][41][42] With the incorporation of Cu, the CuCo-based electrocatalysts display a higher catalytic activity due to their tailored electron transfer between Cu and Co ions.…”

Structural Engineering of Low‐Dimensional Metal–Organic Frameworks: Synthesis, Properties, and Applications

“…Typically, Co 3 O 4 /ZnO nanosheet obtained by calcination of bimetallic 2D CoZn-ZIF, showed uniform dispersion of Co and Zn on the bimetallic oxide nanosheets (Figure 14a-e). [71] Recently, the rationally designed metal coordination complexes, such as Fe-1,4-bis(1H-1,3,7,8-tetraazacyclopenta (1) phenanthren-2-yl) benzene (btcpb) nanosheets, [249] Cu(4,4′-bipy)(NO 3 ) 2 , [250] and Mo-polydopamine nanopetals, [84] have been served as precursors for the preparation of 2D metal-nitrogen doped carbon materials. [71] Recently, the rationally designed metal coordination complexes, such as Fe-1,4-bis(1H-1,3,7,8-tetraazacyclopenta (1) phenanthren-2-yl) benzene (btcpb) nanosheets, [249] Cu(4,4′-bipy)(NO 3 ) 2 , [250] and Mo-polydopamine nanopetals, [84] have been served as precursors for the preparation of 2D metal-nitrogen doped carbon materials.…”

“…[48][49][50] These types of MOFs, such as 1D single-walled MOF nanotubes, 1D hexagonal MOF nanorods, ultrathin 2D MOF nanosheets, [51][52][53] have similar morphological features to those of the other 1D or 2D nanomaterials, which endows them with distinctive dimensional-dependent properties including high aspect ratio and abundant accessible active sites. [60][61][62][63][64][65][66][67][68][69][70][71][72][73][74][75] Although the advantages and challenges of 1D metal-organic nanotubes [76] and 2D MOF nanosheets [48,50,56] have been well summarized by several previous review articles, the research field of LD MOFs is currently at a stage of rapid development, as indicated by annually increased amount of publications (Figure 2). To achieve effective and controllable preparation of LD MOFs, a large number of synthetic methods have been developed, such as template method, ultrasonic exfoliation, surfactant-assisted growth, three-layer method, etc.…”

Rational Design of Holey 2D Nonlayered Transition Metal Carbide/Nitride Heterostructure Nanosheets for Highly Efficient Water Oxidation

“…Transmission electron microscopy (TEM) image ( Figure 1b) confirms a representative 2D thin flake-like feature of the Mo/Zn BIF precursors, recognized by field-emission scanning electron microscopy (FESEM, Figure S1a,b, Supporting Information) and TEM studies ( Figure S1c, Supporting Information). [27] The resulting 2D Mo/Zn BIF were then annealed in N 2 atmosphere at 800-900 °C to enable the pyrolysis of Mo/Zn BIF as a self-template and the formation of molybdenum carbide/nitride nanocrystals, which Adv. [27] The resulting 2D Mo/Zn BIF were then annealed in N 2 atmosphere at 800-900 °C to enable the pyrolysis of Mo/Zn BIF as a self-template and the formation of molybdenum carbide/nitride nanocrystals, which Adv.…”